Glycated hemoglobin (HbA1c): what are we talking about exactly?
Before explaining what glycated hemoglobin is, we must make a detour to the side of the hemoglobin. Hemoglobin is a protein found in red blood cells that circulate in the blood. His role ? It is essential: it is hemoglobin which transports (and releases) oxygen molecules throughout the body to allow the functioning of the various organs – the brain, the heart …
The glucose, meanwhile, is the main “fuel” of the body: this molecule (mainly derived from the sugar provided by the diet) binds irreversibly to hemoglobin and gradually accumulates in red blood cells – that l also called “red blood cells” or “erythrocytes” in medical parlance. “ We can say that sugar “parasitizes” hemoglobin since it modifies its physicochemical properties., explains Pierre Zachary, biologist. When the glucose binds to hemoglobin, this formsglycated hemoglobin or HbA1c. “
In a healthy person, glucose binds only in small amounts to hemoglobin: “ everyone has a small percentage of glycated hemoglobin in their blood, it’s okay “specifies the specialist.
On the other hand, in a diabetic person, the blood level of glycated hemoglobin (expressed as a percentage) is significantly higher because, as explained by the French Federation of Diabetics (FFD), ” more the blood sugar is high, the greater the amount of glucose attached to hemoglobin “Diabetes is a metabolic disease characterized by chronic hyperglycemia.
Glycated hemoglobin (HbA1c): what are the normal values? In a healthy person, a “normal” glycated hemoglobin level in the blood is between 4% and 6%.
Glycated hemoglobin (HbA1c): a tool for monitoring diabetes
To know. The measurement of glycated hemoglobin (HBA1c) is done in the laboratory or in the hospital: a blood test is sufficient, without special precautions – it is not necessary to be on an empty stomach. It should be noted that this medical examination is not part of the “routine assessment” carried out in the laboratory: it is specifically prescribed for patients suffering from diabetes – type 1 or type 2.
While glycemia (that is to say: the measurement of the glucose concentration in the blood, which can be done independently at home using a blood glucose meter or glucometer) corresponds to a ” instantaneous “of the glycemic state of the diabetic patient, the measurement of glycated hemoglobin makes it possible to evaluate his glycemic balance over a longer period (approximately two to three months). Thus, the measurement of HbA1c constitutes a good “tool for monitoring” diabetes.
To know. At the start of treatment, in a patient who has recently been diagnosed with diabetes, glycated hemoglobin will be measured every 3 months using a blood test – because the red blood cells that contain hemoglobin have a lifespan of approximately 120 days.
Depending on the results obtained, the ” the doctor will consider therapeutic adaptations (reinforcement of hygieno-dietetic measures, adaptation of drug treatment, etc.) if necessary “develops the French Federation of Diabetics (FFD).
Type 1 or type 2 diabetes: values for glycated hemoglobin and blood sugar
” Generally, diabetes is considered balanced if the HbA1c level is less than or equal to 7%. Beyond that, the risk of developing long-term complications (nephropathy, retinopathy, cardiovascular diseases, polyneuritis, etc.) increases “specifies the French Federation of Diabetics (FFD).
In detail and according to the recommendations of the French National ity for Health (HAS): in the case of type 2 diabetes, the objective is to fall below the threshold of 7% glycated hemoglobin (HbAc1); in type 1 diabetes, the goal is to go below 7.5%. These values may however vary depending on the patient’s age, the existence of diabetic complications and / or associated diseases (arterial hypertension, obesity, etc.): they must therefore be determined in consultation with the doctor.
Side numbers … Thus, a blood level of glycated hemoglobin of 7% corresponds to an average blood sugar level of 1.5 grams of glucose per liter of blood: 1% more HbA1c represents an average increase in blood sugar of 0.30 g / l .
Thanks to Pierre Zachary, biologist at Biogroup in Strasbourg (67).
Source : French Federation of Diabetics (FFD)